In continued cooperation with Prof. J.M. Cook and his coworkers at the University of Wisconsin-Milwaukee, the synthesis of di-and ploycyclic ring systems composed of fused cyclopentane rings ("polyquinanes") has been developed further. The approach chosen is based on the ready stereosoecific formation of derivatives of cis-bicylo (3.3.0) octane-3.7-dione (1) from 1.2-dicarbonyl compounds and esters of 3-oxoglutaric acid (the "Weiss reaction"). Several more tetracyclic polyquinane ring systems have been synthesized by suitable further transformations of (1) or its closely related analogs. Thus, the first 1, 10-disubstituted derivatives of the long-known, triply unsaturated triquinane triquinacence (R.B. Woodward et al., 1964) have been made, including a novel compound,2, where an additional six-membered ring is fused at these positions of triquinacene. Saturated representatives of several other systems have been prepared as intermediates in the planned synthesis of related compounds with the maximum possible number of double bonds; these latter molecules should be valuable for intended studies of the possible aromatic nature of such compounds.